7 favorite votes.  

Medium yellow Hybrid Tea.
Registration name: Debonair
Exhibition name: Debonair

Bred by Dr. Walter E. Lammerts (United States, 1946).
Introduced in United States by Armstrong Nursery in 1946 as 'Debonair'.
Introduced in Australia by Hazlewood Bros. Pty. Ltd. in 1949 as 'Debonair'.

Hybrid Tea.  

Yellow.  Flowers primrose-yellow.  Moderate fragrance.  28 to 35 petals.  Average diameter 4.5".  Large, full (26-40 petals), exhibition, high-centered bloom form.  Blooms in flushes throughout the season.  Ovoid buds.  

Bushy, upright.  Glossy, dark green, leathery foliage.  

USDA zone 6b through 9b (default).  Can be used for cut flower, exhibition or garden.  Very vigorous.  Protect tender new spring growth from hard freezes that may cause canker, die-back and death of the plant. .  Remove spent blooms to encourage re-bloom.  Spring Pruning: Remove old canes and dead or diseased wood and cut back canes that cross. In warmer climates, cut back the remaining canes by about one-third. In colder areas, you'll probably find you'll have to prune a little more than that.  Remove old canes and dead or diseased wood..  

United States - Patent No: PP 677   VIEW USPTO PATENT